hey bluebird,
to turn stepper drive on en/nopower pin I inverted the signal to low to turn power off because high is on and low is off. (or nopwr) so my step drives are always off, used a Ic to send a low signal to controller, then a high signal from mach to turn back on.( tried a resistor to pull high, and low but my controler did NOT like that. It wants HIGH OR LOW nothing in between, thats whyi used a switching IC
anyways I used the m7 m8 coolant command to turn my x-y on and m9 to turn off at the end of cycle. you may want to pause a few seconds after power on just to make sure it is fully energized before running program. the only problem with doing this is that you have to run a separate m7 m8 command to do a axis home or jog.
The motors really shouldn't get that hot, they run almost as good at a lower power setting, I have small motors so I run them at max amerage, then turn them off.
just a thought??
Steve